Attorney General Greg Abbott said Tuesday that his office’s investigation of a Houston voter registration group that netted no prosecutions but left the organization in tatters was justified.

The 2010 investigation, which included an aggressive raid, targeted a group called Houston Votes, which was accused of voter fraud.

“We have a division that focuses on issues like this, and they operate very professional,” he said. “They undertook an investigation of allegations that were made.”

Abbott, the Republican nominee for governor, unveiled the final piece of his education proposals at the University of Texas at Dallas on Tuesday. Afterward, he told The Dallas Morning News that allegations of wrongdoing by the group started with the Harris County tax assessor-collector’s office, were given to the secretary of state and were forwarded to his office.

He said Houston Votes officials were accused of “inappropriately duplicating registration forms,” comparing its activities to ACORN, the nationally known community organization group that has been beset by allegations of voter registration fraud.

“Houston Votes had to fire more than 10 people for either falsifying or inappropriately duplicating registration forms, so there was some wrongdoing that was akin to ACORN-type political operations that deserved looking into,” Abbott said.

The News reported Sunday that the investigation was closed one year after the previously unreported 2010 raid, with no charges filed. But the funding for Houston Votes dried up, and its efforts to register more low-income voters in Harris County ended.

Its records and office equipment never were returned. Instead, under a 2013 court order obtained by Abbott’s office, they were destroyed.

The raid coincided with a local tea party group’s allegations of widespread voter fraud and the testimony of Fred Lewis, the president of the nonprofit parent group of Houston Votes, in the trial of former U.S. House Majority Leader Tom DeLay, R-Sugar Land.

Lewis had filed a complaint against DeLay that, in large part, led to his indictment on corruption charges.

Lewis said Abbott’s comments were “unwarranted.”

“It was an unprofessional investigation that was politicized. It reflects poorly on the office and the investigators,” he said.

He added that his group “is not ACORN. It has no relationship to it. To bring them up is to beat not only a dead horse, but the wrong horse.”

Abbott’s office opened a criminal investigation into Houston Votes after the secretary of state in September 2010 forwarded it allegations of voter registration fraud from the Harris County tax assessor-collector. Houston Votes had rebutted those allegations.

Lewis told The News he had no proof that Houston Votes employees had violated the law, but said 10 to 15 workers were fired in 2010 for submitting duplicate voter registration applications and making other mistakes.

Critics say Abbott’s motivation in investigating Houston Votes and other voter-registration efforts was to help the Texas GOP maintain political power. They say his investigations target key Democratic voting blocs, especially minorities and the poor, while revealing little fraud.

Abbott said Tuesday that the investigation and raid were carried out without his knowledge.

“I don’t know when I first knew about it,” he said. “It may have been fairly recently. I didn’t know about it at the time it was going on.”

Abbott said he trusted his aides.

“We’ve got hundreds of cases involving that issues and thousands of cases overall,” he said. “I’ve got to put good people in place and have them do a good job.”

Abbott also touted his higher-education proposals, saying he would work to ensure that “more students graduate on time, hold public colleges and universities accountable for student outcomes and leverage technology and online learning.”

Abbott’s plan would implement outcomes-based funding at four-year institutions, establish block scheduling for two-year associate degree programs, adopt a statewide AP credit-by-exam policy requiring public institutions to award college credit to high school students scoring a three or above on AP exams and expand access to online courses and count them toward degree requirements.

It would also fully fund tuition and fees for military families who qualify for exemptions and increase state support for emerging research universities.

Abbott was joined Tuesday by a slew of GOP elected officials, including Rep. Dan Branch, the Dallas Republican who leads the House Higher Education Committee. Much of Abbott’s plan had already been proposed by Branch.

Matt Angle, a strategist for Democratic nominee Wendy Davis, said the plan would help insiders, not students.

“Abbott’s plan is to use public education funds to give profit opportunities to his insider friends and donors, while Texas students get shut out,” Angle said.

Abbott said he hoped his overall education plans would help the state deal with ongoing litigation over school finance. A judge ruled last week that the state doesn’t spend enough to ensure adequate education or spread the funds fairly. Abbott plans to appeal the ruling, likely to the state Supreme Court.

“This is a type of litigation that’s been in the courts for three decades,” he said. “Part of what is needed is additional funding to achieve certain goals. … Just throwing money at it period is no solution.”